Weird rock formations in all shapes and sizes inhabit the northern section of Joshua Tree National Park known as the Wonderland of Rocks. A few official trails including the Boy Scout Trail, Barker Dam, and Wall Street Mill provide some access to the region. With a good map, compass and plenty of water, the visitor can explore any of the side canyons to find little wonders of their own in the worn granite of the area.
Piles of boulders occur where weathering of the solid granite took place underground prior to exposure of the rock to the surface. Above ground, the granite not worn into boulders exhibits great cracks, thought to have formed by expansion as the weight of the overlying rock was removed by erosion. Subsequent further erosion of the granite smooths and opens these cracks, creating the rounded features and eventually cutting off slabs from the larger body of rock.